Science - MRSEC - Northwestern University

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Overview of Northwestern University
and the Materials Research Center
Lincoln Lauhon
RET Program Director
Materials Research Center
Department of Materials Science and Engineering
MRSEC
Northwestern University
• Founded in 1851 to serve the Northwest
Territory, an area that now includes: Ohio,
Indiana, Illinois, Michigan, Wisconsin, and
part of Minnesota.
• In 1853 the founders purchased a 379-acre
tract of land on the shore of Lake Michigan
12 miles north of Chicago.
• They established a campus and developed the land near it, naming the
surrounding town Evanston in honor of one of the University's founders,
John Evans.
• After completing its first building in 1855, Northwestern began classes
that fall with two faculty members and 10 students.
• Currently two campuses: a 240-acre campus in Evanston, and a 25-acre
campus in Chicago.
• Annual Budget ~$1.2 Billion (51% from tuition, 31% from grants)
Source: http://www.northwestern.edu/about/facts/
MRSEC
Northwestern: Student Body
• 7,976 undergraduates
– 4,058 in Weinberg College of Arts
and Sciences
– 1,381 in McCormick School of
Engineering and Applied Science
• 7,153 graduate and professional
students
– 1,162 in Weinberg College of Arts
and Sciences
– 726 in McCormick School of
Engineering and Applied Science
Source: http://www.northwestern.edu/about/facts/
MRSEC
Northwestern: Faculty and Research
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Approximately 2,500 full-time faculty
Approximately 4,600 staff
607 in Weinberg College of Arts and Sciences
187 in McCormick School of Engineering and Applied
Science
• 2007 total research budget $416 million
– 72% Federal Sources (11.6% NSF)
– 13.7% McCormick Engineering
– 11.6% Weinberg Arts and Sciences
– 6.4% Research Centers
Source: http://www.northwestern.edu/about/facts/
http://www.research.northwestern.edu/publications/annual-report/2007/AR2007.pdf
MRSEC
Northwestern: Engineering
McCormick School of Engineering and Applied
Science Departments:
– Biomedical Engineering
– Chemical and Biological Engineering
– Civil and Environmental Engineering
– Electrical Engineering and Computer
Science
– Engineering Sciences and Applied
Mathematics
– Industrial Engineering and Management
Sciences
– Materials Science and Engineering
– Mechanical Engineering
MRSEC
Northwestern: Science
Weinberg College of Arts and Sciences (Departments and Programs)
– biochemistry, molecular biology, and cell biology
– biological sciences
– chemistry
– computing and information systems
– earth & planetary sciences
– environmental sciences
– integrated science program
– interdepartmental biological sciences program (iBis), grad program
– mathematics
– neurobiology and physiology
– physics and astronomy
– plant biology and conservation
– statistics
MRSEC
Northwestern: Research Centers
• Northwestern supports interdisciplinary research through Research
Centers, which are independent of schools
• List of Science and Engineering-related Centers:
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Argonne/Northwestern Solar Energy Research Center
Center for Catalysis and Surface Science
Center for Drug Discovery and Chemical Biology
Center for Functional Genomics
Center for Reproductive Science
Center for Sleep and Circadian Biology
Center for Cancer Nanotechnology Excellence
Chemistry of Life Processes Institute
Institute for Bionanotechnology in Medicine
International Institute for Nanotechnology
Materials Research Center
Nanoscale Science and Engineering Center
Northwestern Institute on Complex Systems
Northwestern Synchrotron Research Center
Northwestern University Atomic and Nanoscale Characterization Experimental
MRSEC
Center
Materials Research Center
• Started in 1960
• Funding originally from Department of Defense
• Now funded by the National Science Foundation
under the Materials Research Science
and Engineering (MRSEC) program
• 36 faculty members from 8 academic
departments
• 18 postdocs, 68 graduate students
• Budget: approximately $2-3 million per year
• 6-year renewal funding cycle
MRSEC
NU-MRSEC Mission
The Northwestern University Materials
Research Science and Engineering
Center develops and supports
collaborative, interdisciplinary research
and education in the science and
engineering of nano-scale
multifunctional material structures.
MRSEC
Synergistic, Innovative Research
• Research organized into Interdisciplinary Research Groups (IRGs)
• IRG 1 Synergistic Linear and Nonlinear Phenomena in
Multifunctional Oxide Ceramic Systems
• IRG 2 Novel Processing Methods for Nanostructured Polymer
Blends, Composites and Supramolecular Structures
• IRG 3 Molecular Plasmonics: Fundamentals, New Tools, and
Devices
• IRG 4 Hybrid Organic-Inorganic Nanoelectronic Materials from
Molecules to Printable Thin Films
• Groups of 6-10 researchers from various academic
departments work on a complex set of problems
for several years
• Significant theory-experiment interactions
• High-risk new project funded as Seeds
• Currently, biology-related and biomaterials research
MRSEC
Research Goals
IRG #1: Synergistic Linear and Nonlinear
Phenomena in Multifunctional Oxide Ceramic
Systems
GOAL OF IRG #1:
This group seeks to advance fundamental
knowledge leading to the development of energyefficient and novel multifunctional devices for
electronic, optoelectronic, storage, sensor and
information technologies.
MRSEC
Mixed Metal Oxide Chalcogenides
Evan Stampler , Kenneth Poeppelmeier
Mixed metal oxide chalcogenides find utility in a variety of
areas, including transparent conductors. BiCuOSe was
prepared at low temperature (250 oC) and pressure (< 20
atm) and the experimental parameters (pH, temperature,
reagents, etc.) conducive to the hydrothermal preparation
of oxide chalcogenides were explored.
Scanning electron
microscope image of
mixed metal oxide
chalcogenide.
Isosurface of the electron
localization function (ELF)
illustrates the directional lone pair
(orbital mixing) on bismuth cations
(black sphere) near the
chalcogenide (green sphere)
anions.
MRSEC
Molecular Beam Epitaxy of Ferroic and
Multiferroic Thin Films
Ji Cheng, G. Sterbinsky, B. W. Wessels, Sujing Xie and Vinayak P. Dravid
Fig
1A 1A:
Figure
Epitaxial ferroic oxide thin films and multilayers have
been synthesized by oxide molecular beam epitaxy
(MBE), for combining materials with different
properties such as ferromagnetism and
ferroelectricity in a single structure.
Fe3O4, CoFe2O4 and MgFe2O4 were deposited,
which exhibit sharp interfaces with excellent cubeon-cube orientation.
Fig. 1A: Cross-section HRTEM of epitaxial CoFe2O4 film on
SrTiO3 substrate, showing sharp interfaces with cube-oncube orientation; Fig. 1B: In-plane MOKE hysteresis loops
of Fe3O4 and MgFe2O4 films.
20
Fig 1B
15
MOKE ellipticity (mdeg)
Magneto-optic Kerr effect (MOKE) and SQUID
magnetometry measurements indicate that bulk-like
magnetic properties can be obtained in the thin films.
25
Fe
/MgO
Fe3O3O
/MgO
4 4
10
5
0
-5
MgFe O
O /MgO
MgFe
2 4/MgO
2
-10
4
-15
-20
-25
-0.4
-0.3
-0.2
-0.1
0.0
0.1
Magnetic field (T)
0.2
0.3
0.4
MRSEC
Research Goals
IRG #2: Novel Processing Methods for
Nanostructured Polymer Blends, Composites and
Supramolecular Structures
GOAL OF IRG #2:
The primary goal of this group is to develop and
produce materials with superior mechanical
properties using polymer-based processing
strategies that include polymers, ceramics, metals
and structured composite materials.
MRSEC
A Reliable Strategy for Designing Functional Polymer
Nanoparticles Using Ring-Opening Metathesis Polymerization
Jun-Hyun Kim and SonBinh T. Nguyen
We have developed a highly reliable approach
for the preparation of functional polymeric
materials utilizing ring-opening metathesis
polymerization (ROMP). Examining the
chemical/physical properties of these functional
norbornene-based homopolymers will lead to a
better understanding of the changes in their
properties upon incorporation with inorganic
materials (SiO2, gold, and/or Fe2O3). The
resulting nanocomposites can then serve as
environmental responsive materials for coatings,
mechanical reinforcement, electro-optical
applications and biological delivery.
SEM images of poly(NBE-COOH) in various solvents
MRSEC
Mystery of Charge Asymmetry: Anionic Macroions in Periodic
Lattices Held by Hydrated Cations and Not Vice-versa
William Kung, Dongsheng Zhang, Pedro Gonzales-Mozuelos, Monica Olvera de la Cruz
Experiments have shown that negatively charged colloids experience a long-range attraction and
spontaneously order in a solution of counterions, but positively charged colloids do not order under
similar circumstances. This asymmetry can be understood in terms of the bent geometry of water
molecules as shown in the diagram on the
right. There is frustration in the arrangement
of water molecules around neighboring likecharged particles in (A) and (B). Due to the
bent-core geometry of the water molecules,
they arrange themselves in a more favorable
configuration for larger negative particles with
smaller positively charged particles (C) than in
the reverse scenario (D). A mean-field
analytical model and numerical simulations
(LEFT) Interactions
were applied to a colloidal system of
between the bent-core
negatively charged disks and counterions that
water molecules (blue) and
are absorbed on an interface in a
the positive and negative
compressible binary system. The system
particles.
(ABOVE): Simulation
results in a dilute isotropic ionic phase and a
snapshots of the counterion
condensed hexagonal lattice phase.
(small dot) - colloid (red)
interactions.
MRSEC
Research Goals
IRG #3: Molecular Plasmonics: Fundamentals, New
Tools, and Devices
GOAL OF IRG #3:
The primary goal of this group is to advance
understanding of plasmonic phenomena at the
single nanoparticle and single molecule levels; and
to develop the new research tools necessary to
accomplish this.
MRSEC
Plasmonic Properties of Aluminum Nanoparticles
Fabricated by Nanosphere Lithography
George H. Chan, Jing Zhao, George C. Schatz, and Richard P. Van Duyne
A plasmon is the result of light interacting
with the surface electrons in materials that
meet specific dielectric requirements. Noble
metals have long been used as plasmonic
materials, yet other materials are capable
of supporting surface plasmons. Recent
work in the Van Duyne lab has shown that
aluminum nanoparticles fabricated using a
process known as nanosphere lithography
(NSL) display plasmons throughout the UVvis region. Both from experiment and
theory, the presence of an oxide layer does
not significantly affect their plasmonic
properties. As a result, a promising
plasmonic active UV material has been
developed for use in surface enhanced
spectroscopies (i.e., Raman) and in
plasmonic devices.
MRSEC
Nanodisk Codes
Lidong Qin, Matthew J. Banholzer, Jill E. Millstone, and Chad A. Mirkin
Researchers at Northwestern University
b)
have developed a method to use
a)
nanoscale disk arrays as powerful
encoding devices that can be dispersed
in a variety of materials for both security
and sensing applications. These
Nanodisk Codes (NDCs) are made using
c)
a process called “On-Wire Lithography”
which can create a linear series of disk
pairs, each with a tiny gap. These disk
pairs amplify molecular signals so that the
2D Confocal Raman Image
NDC can be read out both by counting
the number of disks along an individual
array or by identify the chemical signal
broadcast from and amplified by the disk
pair. It is possible to make billions of
3D Confocal Raman Image
unique codes simply by increasing the
a) Nanodisk fabrication. b) Multi-level encoding based on binary
number of disk pairs and/or type of
readout and disk functionalization. c) Harnesses the power of
molecular signal.
nanostructured Raman “hot spots,” greatly enhancing intrinsic
Nano Lett., 7, 3849 (2007).
Raman signal by 8 orders of magnitude.
MRSEC
Research Goals
IRG #4 Hybrid Organic-Inorganic Nanoelectronic Materials
from Molecules to Printable Thin Films
GOAL OF IRG #4:
Synthesis, processing, characterization and theory will be
employed to improve fundamental understanding and
optimize process efficiency across multiple length-scales,
and to enable novel technological advances in the area of
hybrid organic/inorganic nanoelectronic materials.
MRSEC
Detection of Single Gold Atoms in Silicon Nanowires
Jonathan E. Allen, Eric R. Hemesath, Daniel E. Perea, Jessica L. Lensch-Falk, and Lincoln J. Lauhon
Semiconductor nanowires grown with
metal nanocatalysts are new materials that
provide a basis for transformative
improvements in diverse technologies
including thermoelectrics and
photovoltaics. Nanowire electronic
properties depend strongly on
incorporated impurity atoms, which have
not been previously observed.
Northwestern researchers and their
collaborators have imaged single gold
catalyst atoms in individual silicon
nanowires, and measured the influence of
the gold on the electrical properties.
Scanning transmission electron microscope
image of lines of single gold atoms in a
twinned silicon nanowire.
International collaborators: Richard E. Palmer, Ziyou Li, Feng Yin, University of Birmingham,
and Mhairi H. Gass, Peng Wang, and Andrew L. Bleloch, SuperSTEM Laboratory, Daresbury.
Nature Nanotechnology, 3, 168 (2008).
MRSEC
Atomic Force Photovoltaic Microscopy
B. J. Leever, M. F. Durstock, M. D. Irwin, A. W. Hains, T. J. Marks, L. S. C. Pingree, and M. C. Hersam
Organic photovoltaic devices (OPVs)
hold promise for a variety of
applications requiring alternative energy
generation. Through a collaboration
between Northwestern University
MRSEC IRG 4 and Wright Patterson Air
Force Base, a new strategy for
characterizing the electrical and optical
performance of operating OPVs has
recently been developed. Atomic force
photovoltaic microscopy allows the
photocurrent response in OPVs and
other optoelectronically-active materials
and devices to be spatially mapped
down to the nanometer length scale.
Atomic force photovoltaic microscopy
image of the short circuit response of an
array of illuminated organic solar cells.
Appl. Phys. Lett., 92, 013302 (2008).
MRSEC
Seed Projects
Seed funding is provided to promising new high-risk projects that
may result in transformative science.
• Seed #1 – Synthetic Development of Novel Organic Electron
Transport Materials (Karl A. Scheidt, Chemistry)
• Seed #2 – Nanocomposite Elastomers for Vascular Tissue
Engineering (Guillermo Ameer, Biomedical Engineering)
• Seed #3 – Analysis and Design of Genetic and Metabolic Control
Systems of Bacterial Cells (Adilson E. Motter, Physics and Astronomy,
John F. Marko, Biochemistry, Molecular Biology & Cell Biology, Physics
and Astronomy)
• Seed #4 – Electrostatically “Patchy” Nanoparticle Coatings for
Applications in Biomaterials and Flexible Electronics (Bartosz Andrzej
von Poray Grzybowski, Chemical and Biological Engineering)
MRSEC
Moldable Supraspheres Made of Metal Nanoparticles
R. Klajn, K. J. M. Bishop, C. J. Campbell, B. A. Grzybowski
Metal nanoparticles crosslinked by dithiol
linkers form “supraspherical” assemblies
that behave like Play-doh and can glue to
one another to form macroscopic materials.
Researchers at the Northwestern
University MRSEC have shown that such
materials combine the properties of plastics
and metals.
Due to their “stickiness”, the supraspheres
can be molded at room temperature into
macroscopic structures of arbitrary shapes.
Subsequent gentle heating hardens the
objects and converts them to pure-metal
monoliths. This general strategy has been
successfully extended to various noble
metals and their alloys.
The picture on the left shows
supraspheres – that is, buildling
blocks of “moldable metals”. The
picture on the right shows a
macroscopic (1 mm-wide) gear
molded at room temperature and
“hardened” by heating at 50 oC.
Science, 316, 261 (2007).
MRSEC
Magnetic Tweezer System for Single-DNA Experiments:
A Summer Undergraduate Project
James Kath (REU), John Graham (Mentor) and John F. Marko
REU student James Kath, under the supervision
of Professor John Marko has constructed a
magnetic tweezer system which allows forceextension and twisting experiments to be carried
out on single DNA molecules. The primary
application of this instrument will be to the study
of protein-DNA interactions.
Preliminary studies have verified that the new
instrument can carry out rapid acquisition of
extensions of DNA molecules, via particletracking and out-of-focus bead image analysis.
This simple instrument can monitor motions of
paramagnetic colloidal particles attached to DNA
molecules in three dimensions.
REU participant, James Kath constructs microscope
which uses optical microscopy to monitor motions of
magnetic particles attached to DNA molecules.
Particles are pulled and rotated using permanent
magnets on a positioner.
MRSEC
Shared Facilities, Labs and Equipment
Labs
• Center manages 15 shared facilities
• Shared experimental facilities
available to on and off-campus
researchers
• 25,000 sq. ft.
• operations funded through grants
and user fees
Equipment
• 500 faculty and students use the
equipment
• Most of the equipment is housed in
MRC
• Equipment Cost Budget
• Equipment purchases or upgrades
http://www.mrsec.northwestern.edu/content/facilities/index.htm
MRSEC
International Collaborations
Ajou University, Korea
• Brain Korea 21 (BK21) is a research-oriented
educational program between Ajou University and
the Materials Research Center.
• NU Collaborators: Mark Hersam, John Torkelson
• Dr. Jae-Ho Kim development of mass production
technology of carbon nanotube atomic force
microscope tip.
• Jae-Hyeok Lee spent three months in 2008 at NU
studying carbon nanotube atomic force microscope
tips with the Hersam group.
University of Riga, Latvia
• Institute of Solid State Physics
• Collaboration on theoretical calculations of defects
in crystalline metal oxides.
• NU Collaborator: Don Ellis
• Scientists from Latvia visit NU several times a year.
MRSEC
Industry / National Lab Interface
Workshops/ Seminars/Colloquia
• Symposium on Atomic-Scale Modeling (July 25)
• Mark Stevens, Sandia (July 26)
• “Optically/Electronically Functional Polymers and
Molecular Assemblies” Colloquium Series
Student Internships
• NREL (Mariana Bertoni), transition metal oxides
• New: Sigma Aldrich
Visitors
• Industrial visitors in Torkelson lab: SSSP
• Visitors attending workshops, meetings
• Use of Shared Facilities
Licensing of patents through Technology Transfer
Office.
MRSEC
Educational Programs
• Middle School Science Clubs
– About weekly October - May
– Undergraduate, graduate student
volunteers
• Sponsor: Science in the Classroom
(elementary school); NU Solar Car Team
• Center for Talent Development summer
class for middle school students: Materials
and Engineering Design Honors
• Academic-year Undergraduate Research
Internship
• Summer Research Experience for
Undergraduates (REU), Research
Experience for Teachers (RET)
MRSEC
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